This paper focuses on Plotinus’ account of the soul’s cognitive powers of sense perception and discursive thought, with particular reference to the treatises 3. 6 [26], 4. 4 [28] and 5. 3 [49] of the Enneads . Part 1 of the paper discusses Plotinus’ direct realism in perception. Parts 2 and 3 focus on Plotinus’ account of knowledge in Enneads 5. 3 [49] 2–3. Plotinus there argues that we make judgements regarding how the external world is by means of discursive (...) reasoning. This latter claim, however, is in tension with what Plotinus argues elsewhere regarding our perceptual apprehension of the external world (3. 6 [26] 1; 4. 4 [28] 23). This puzzle is addressed in Part 3 of the paper, which investigates Plotinus’ view that there exist some sense perceptions of which we are unaware. Finally, Part 4 looks at Plotinus’ understanding of Plato’s famous wax block analogy, in 5. 3 (49). The overall conclusion of the paper is that Plotinus’ account of knowledge is radically different from that of the Cartesian tradition. (shrink)